Integrated Dynamics Control System With ESC and RAS for a Distributed Electric Vehicle

An integrated control system developed for improving the vehicle handling and stability under critical lateral motions that includes electric-stability-controller (ESC) and rear-wheel-active-steering (RAS) systems and coordinates the ESC and RAS controllers based on the β-β̇ phase plane method is discussed in this paper. The ESC includes a fuzzy logical controller that calculates the yaw moment and an additional rear wheel steering angle based on the vehicle steering states. The RAS control system consists of two parts: a feedback controller and a feed-forward controller. When the vehicle in the normal driving situations, the RAS system provides enhanced handling performance. If the vehicle reaches its handling limits, then both ESC and RAS are integrated to ensure vehicle stability. The simulation results demonstrated that the proposed integrated controller system not only can resist external interference and reduce driver fatigue but also improves both vehicle stability and handling.